1. Field of the Invention
The present invention relates to an improvement in a camera including a format selecting means for selecting a given one of full size photographing and photographing in a print format different from the full size.
2. Related Background Art
Recently, a camera capable of photographing in a print format (panorama size) different from a normal full size, such as panorama photographs, has been put into practical use. A photographer can perform selection between a normal full size and an arbitrary scene size in the same camera by selecting this size.
On the other hand, there is provided a camera by which distances to a plurality of positions within an angle of view at which photographing is to be performed can be measured by a distance measuring device. In an active device of this sort, the direction of a projected beam corresponds to a distance measuring position. A plurality of light projection elements are fixed in different directions, and position detection elements (PSD) corresponding to the individual directions are arranged. This makes it possible to measure distances to a plurality of positions.
If photographing in different print formats is possible in the camera capable of measuring distances to a plurality of positions, however, the same distance measuring point selection scheme as in full size photographing is also used in panorama size photographing. This results in the following problems.
1) A distance measuring point for a photographing angle of view is set at a position where it is assumed on the basis of data of conventional full size photographing that a probability of the presence of a principal object to be photographed is high. In a practical situation, therefore, in panorama size photographing which is different in photographing magnification, the distance measuring point is not located at an appropriate position; the distance measuring point is located on a background or the like rather than the principal object to be photographed.
2) An operating means for determining a driving direction and a driving amount of a focusing lens on the basis of data obtained by measuring distances to individual distance measuring points, i.e., an operating means for calculating a point which is to be focused performs the operations in accordance with an operation method suitable for full size photographing in which a probability that an object to be photographed is present at the center of a scene is high. In panorama size photographing, a probability that a principal object to be photographed is present at the center of a scene is lower than that in full size photographing. Therefore, a distance measuring point other than the one at the center corresponds to a principal object to be photographed. In this case, even if proper distance measurement data is output, arithmetic operations are executed by the method suitable for full size photographing. Consequently, there is a high possibility that the operation result is determined by data corresponding to distance measurement for a background which is positioned at the distance measuring point at the center.
Of compact cameras incorporating a zoom lens, a camera in which a photographing optical system is changed for macro photographing on the most telephoto side is known. This camera can perform photographing corresponding to object distances within a predetermined range from the wide-angle side to the telephoto side in a normal zoom region. When a macro mode is set, the camera can photograph an object in a certain designated distance closer than the predetermined range.
FIG. 17 is a side view showing an optical system in such a macro photographing state, and FIG. 16 is a side view showing an optical system in a normal photographing state. The macro photographing state is set when a photographic lens barrel 812 is extended forward farther than in the normal photographing state. Referring to FIGS. 16 and 17, the camera consists of viewfinder objective lenses 808 and 809, a photographing scene changing mechanism 804, a viewfinder field frame 804a, and a viewfinder eyepiece 811.
In a camera in which a photographing optical axis and a viewfinder optical axis are arranged apart from each other, as in the compact camera incorporating a zoom lens as shown in FIGS. 16 and 17, a shift is present between a photographing field 813 and a viewfinder field 807. A shift amount is of no problem when an object to be photographed is in a middle or long distance. If, however, an object is at close range as in the macro mode, a scene viewed through a viewfinder is not photographed. Therefore, as shown in FIGS. 18 and 19, short distance correction marks 802a, 802b, and 802c are drawn in the viewfinder field 807, thereby designating the photographing field 813 at the closest focusing distance.
In the camera capable of photographing in different print formats described above, however, the field of the viewfinder is covered with the viewfinder field frame 804a in the panorama mode as shown in FIG. 19, forming a wide field of view corresponding to the range of panorama photographing. In this case, a photographing field in the macro mode (at the closest focusing distance) is as indicated by 814. Although the shift amount from the viewfinder field frame 804a remains unchanged, the ratio of a vertical shift increases because the photographing field is narrowed in the vertical direction. Therefore, as shown in FIG. 19, more than one-half of a scene viewed through the viewfinder is not photographed. That is, there is a large shift amount between a photographing scene that a photographer intends, i.e., a viewfinder field, and an actual photographing field.